Connected: An Internet Encyclopedia
RFC 1072 - 3.5 Generating the SACK Option

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### 3.5 Generating the SACK Option

Let us assume that the data receiver maintains a queue of valid segments that it has neither passed to the user nor acknowledged because of earlier missing data, and that this queue is ordered by starting sequence number. Computation of the SACK option can be done with one pass down this queue. Segments that occupy contiguous sequence space are aggregated into a single SACK block, and each gap in the sequence space (except a gap that is terminated by the right window edge) triggers the start of a new SACK block. If this algorithm defines more than 10 blocks, only the first 10 can be included in the option.

Next: 3.6 Interpreting the SACK Option

Connected: An Internet Encyclopedia
RFC 1072 - 3.5 Generating the SACK Option